Heat sinks have become an important element in computer systems. As the processors in the systems have become faster, they also use more power, and thus generate more heat. Thus, heat sinks increase the surface area of the processors, and allow more heat to be dissipated from the processors.
To provide a good thermal conduction path with the processor, heat sinks are typically compressed downward onto the processor in their attachment with the processor. A tight fit with the processor ensures a conduction path. This arrangement operates quite satisfactorily for processors that are attached to the board via sockets. This type of attachment can withstand a relatively large compressive force.
However, another type of attachment is a ball grid array. With this type of attachment, the processor is soldered to board, with the solder connected being formed from a plurality of solder balls that are placed into a grid array. This type of attachment cannot withstand a relatively large compressive force. If a large force was to be applied to the processor, it would break the solder connections.